Solve the following expression and give your answer as a fraction. $ -\dfrac{29}{100} \times -\dfrac{21}{25} \times -0.4 = {?} $
Solution: First get all of the numbers as simplified fractions. $ -0.4 = -\dfrac{4}{10} = -\dfrac{2}{5} $ Now we have: $ -\dfrac{29}{100} \times -\dfrac{21}{25} \times -\dfrac{2}{5} = {?} $ $ \phantom{ -\dfrac{29}{100} \times -\dfrac{21}{25} \times -\dfrac{2}{5}} = \dfrac{-29 \times -21 \times -2} {100 \times 25 \times 5} $ $ \phantom{ -\dfrac{29}{100} \times -\dfrac{21}{25} \times -\dfrac{2}{5}} = -\dfrac{1218}{12500} = -\dfrac{609}{6250} $